"The sponge is a creature which lives in many parts of the world, and is regularly harvested in the Gulf of Mexico. This little fellow has no heart, brain, liver, bones, and hardly anything else. Some sponges grow to several feet in diameter; yet you can take one, cut it up in pieces, and squeeze it through silk cloth, thus separating every cell from every other cell, and then throw part or all of the mash back into seawater. The cells will all unite back into a sponge! yet a sponge is not a haphazard arrangement of cells; it is a complicated structure of openings, channels, and more besides.

Yes, we said they have no brains; but now consider what they do: Without any brains to guide him, the male sponge knowsÃ¢â‚¬â€to the very minuteÃ¢â‚¬â€when the tide is about to begin coming in. Immediately he releases seed into the water and the tide carries them in. The female sponge may be half a mile away, but she is smart enough (without having any more brains than he has) to know that there are seeds from the male above her in the water. Immediately recognizing this, she releases thousands of eggs which float upward like a cloud and meet the male sperm. The eggs are fertilized and new baby sponges are eventually produced. Really, now, Uncle Charlie, you never explained the origin of the species. Can you explain anything else about them?"

This is a very good point. So I guess the sponges that didn't evolve to come back together and didn't know where to recieve the seeds from the tide died out and by some completely naturalistic way some sponges did; even without a brain. Not buying it.

So I guess the sponges that didn't evolve to come back together and didn't know where to recieve the seeds from the tide died out and by some completely naturalistic way some sponges did; even without a brain. Not buying it.

So what's your point? Not sure I understand what you're trying to say here...

Usually people refer to evolution as an elimination process. I ask why the certain butterflies with "eyes" on their wings have "eyes" and the answer is something like "because those that did survived and those that didn't didn't survive." So does the sponges abilities apply to that same rule?

"The sponge is a creature which lives in many parts of the world, and is regularly harvested in the Gulf of Mexico. This little fellow has no heart, brain, liver, bones, and hardly anything else. Some sponges grow to several feet in diameter; yet you can take one, cut it up in pieces, and squeeze it through silk cloth, thus separating every cell from every other cell, and then throw part or all of the mash back into seawater. The cells will all unite back into a sponge! yet a sponge is not a haphazard arrangement of cells; it is a complicated structure of openings, channels, and more besides."

Sponges are the simplest of animals, and their cells retain a good deal of their choanoflagellate ancestry, being able to exist and function for a time as single entities. But there are other, even more unicellular organisms such as slime molds which spend most of their time as unicellular organisms, and only occasionally aggregate into a mullticellular being. Sponges are a bit more evolved in that direction, but there is a continuum of "multicellularity" in nature.

If things are to evolve, there would have to be. Some of them have persisted and still exist today.

"Yes, we said they have no brains; but now consider what they do: Without any brains to guide him, the male sponge knowsÃ¢â‚¬â€to the very minuteÃ¢â‚¬â€when the tide is about to begin coming in."

They don't know. Like plants, simple physical or chemical signals trigger a physiologic response in sponges. Sponges that evolved such responses were more likely to leave offspring. There are a lot of organisms that just evolve life cycles tied to the cycle of tides. Most use spring tides for reproduction.

"The sponge is a creature which lives in many parts of the world, and is regularly harvested in the Gulf of Mexico. This little fellow has no heart, brain, liver, bones, and hardly anything else. Some sponges grow to several feet in diameter; yet you can take one, cut it up in pieces, and squeeze it through silk cloth, thus separating every cell from every other cell, and then throw part or all of the mash back into seawater. The cells will all unite back into a sponge! yet a sponge is not a haphazard arrangement of cells; it is a complicated structure of openings, channels, and more besides.

This is a very good point. So I guess the sponges that didn't evolve to come back together and didn't know where to recieve the seeds from the tide died out and by some completely naturalistic way some sponges did; even without a brain. Not buying it.

Sponges are not alone with this ability, the Ã¢â‚¬ËœPortuguese Man-O-WarÃ¢â‚¬â„¢ can be separated and then reconstitute itself upon contact with others of the colony (via chemical instructions I suspect), the Portuguese Man-O-War has cells that specialise in stingers, air bladders, tentacles etc. In a way these types of colonies represent an alternate solution to body building. But looking at it dispassionately it just another solution to survival.

Usually people refer to evolution as an elimination process. I ask why the certain butterflies with "eyes" on their wings have "eyes" and the answer is something like "because those that did survived and those that didn't didn't survive." So does the sponges abilities apply to that same rule?

Let's pull back for a second. Do your kidney cells "know" that they are supposed to grab certain salts from the blood stream and move them into your bladder? No, it is a chemical reaction caused by the proteins in the kidney cell. The same for the sponges. They are able to sense the tide which triggers the release of gametes. It need not be a conscious decision, just like the osmotic transfer in kidney cells. How do muscle cells "know" to contract when they recieve a nerve impulse? How do blood cells "know" that they are supposed to exchange oxygen and carbon dioxide?

But yet it wouldneed to adapt according to evolution. How would there be an adaption process to long distance mating?

The just so story:

It is very possible that they only mated over short distances. Small adaptations that allowed the sponges to cover a larger area more quickly was selected for. Over time, this resulted in the long distance mating we see now.

It is very possible that they only mated over short distances. Small adaptations that allowed the sponges to cover a larger area more quickly was selected for. Over time, this resulted in the long distance mating we see now.

It is very possible that they only mated over short distances. Small adaptations that allowed the sponges to cover a larger area more quickly was selected for. Over time, this resulted in the long distance mating we see now.

Why wouldn't the mating strategy work just fine when the male and female sponges were side by side? If all the female has to do is sense gametes in the water, does it really matter where they were released from, be it 1/2 a foot or a 1/2 a mile?

Why wouldn't the mating strategy work just fine when the male and female sponges were side by side? If all the female has to do is sense gametes in the water, does it really matter where they were released from, be it 1/2 a foot or a 1/2 a mile?

"Yes, we said they have no brains; but now consider what they do: Without any brains to guide him, the male sponge knows to the very minute when the tide is about to begin coming in."

The article was obviously written by someone who didn't take the trouble to avail himself of the wealth of information we all now have at our fingertips. If he had, his choice of words might have reflected better comprehension of the nuances of reproduction in sponges, including the fact that most of them are hermaphrodites, and are capable of both S@xual and asexual reproduction. Really, a few minutes of searching is all it would have taken:

"Male gametes are released into the water by a sponge and taken into the pore systems of its neighbors in the same way as food items. Spermatozoa are "captured" by collar cells, which then lose their collars and transform into specialized, amoeba-like cells that carry the spermatozoa to the eggs."

S@xual reproduction in many organisms is often timed to environmental cues such as temperature, tides, hours of daylight, and phases of the moon. Why should sponge reproduction be considered any more mysterious than plants releasing copious quantities of pollen to take their chances in the wind?